1. Field of the Invention
The present invention relates generally to a mechanical/electrical belt scale frame used on belt conveyors for the purpose of monitoring the amount of material that is delivered by the conveyor.
2. Description of the Prior Art
It can be appreciated that belt scales have been used for many years for the purpose of recording and monitoring the amount of material that goes across a conveyor. Typically, these belt scale frames have been manufactured in many different configurations to incorporate existing idlers on the conveyor or to use a supplied idler. The weight detecting electrical sensor, referred to as a load cell or strain gauge, was also attached to the belt scale frame in many different ways. Some frames even incorporated linear variable differential transformers (LVDT) instead of load cells. In all previous belt scale frames, it was necessary to attach these frames directly to the main conveyor frame where the existing conveyor idlers were also attached.
The main problem with a conventional belt scale frame is that its installation would require existing conveyor idlers to be removed and/or modified by cutting, drilling or welding. More than that, in a conventional belt scale frame with a supplied idler, an existing conveyor idler would still have to be removed. Another problem with the current belt scale frames is that once the frame is installed on the conveyor, it would be necessary to shim the existing idlers before and after the scale frame so as to make all the idlers level with one another. Still another problem is the time it takes to actually install a belt scale frame, let alone move the belt scale frame from one conveyor to another.
While all of these devices and circumstances of mounting may be suitable for the particular purpose to which they are applied, they are not as convenient as the present invention. There are many problems that arise when a conventional belt scale frame is to be installed. One problem is that a skilled person is required for cutting or welding an existing conveyor idler to be used on the belt scale frame. Another problem arises if holes need to be drilled in the conveyor frame for the belt scale frame. Yet another problem is removing existing idlers for the purpose of leveling.
Maintenance raises additional problems. For example, due to normal wear and tear, present frames would require removal of the idler. Furthermore, if the belt scale frame were to be removed from the conveyor, a new or used idler that was not modified would need to be re-installed where the belt scale frame had been. Another problem arises where cross supports on the conveyor may need to be removed so that the belt scale frame could set in. Finally, a problem arises if the conveyor on which a belt scale frame was to be installed had a continuous cover between the troughing and return side of the belt, such cover may have to be removed for the belt scale frame to fit.
In these respects, the present invention substantially departs from the conventional concepts and designs of the prior art, and in doing so provides a simpler belt scale apparatus and a simpler method of installing a belt scale on a conveyor.